2- Dust particles emission:

Now when each part of the house is broken, the emission of particles called “dust particles” is triggered. They are emitted with almost 180 degrees variation in direction and with a variation in speed as well.

Emission of “Dust particles” is triggered.

3- Fume emission:
FumeFX uses Dust particles as particle emitters  to create the final look of the dust. There are 2 groups of dust particles, one with high density and low velocity and the other with the opposite. This eliminated the mushroom effects that happens when emitting fluids with high velocity.

The properties of the fluid were that of heavy or cold gas (negative buoyancy or negative temperature) but with no dissipation. The house and the ground are added to to the FumeFX simulation as collision objects so that their velocities affect the behaviour of the fluid.

4- Rendering:
The dust pass was rendered as a RGB pass like the picture below on the left, but with holdouts (matte objects). It was then graded (colored) by the compositors. The red channel represents the key light, blue represents the fill light. I basically used 2 lights, pure red and pure blue. Both channels were colored separately then added together. This gives more control in the compositing phase. The green channel was used as a mask to separate a different kind of dust (dust from chimney) to be color corrected.

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RGB render                                                                Graded in comp.